Spatial Distribution and Diversity of Adiantum capillus-veneris L. and Diplazium esculentum (Retz.) Sw. in Cross River National Park, Erokut Camp, Akamkpa

Abstract

Ferns play a crucial role in tropical forests by offering various ecosystem services; however, the spatial distribution and diversity of Adiantum capillus-veneris L. and Diplazium esculentum (Retz.) Sw has not been recorded in Erokut Camp of Cross River National Park. For this study, ten plots were established, each measuring 10 × 10 m². The research utilized a non-random preferential sampling approach, where all fern species found within each plot were collected, identified, and documented. The collected ferns were identified using taxonomic literature, available materials, and consultation with experts in the field of Taxonomy, while the conservation status of each identified fern species was evaluated based on the recent IUCN 2023 Red List. Voucher specimens were stored in the Herbarium of the University of Cross River State (UNICROSS) in Calabar. The individuals of both species were mapped using a Global Positioning System (GPS) device. Location and attribute queries were produced using the map and coordinates from the study area to verify the accuracy of the data gathered. In total, two hundred and thirty-four (234) individuals of the two species were surveyed in the area, with A. capillus-veneris exhibiting a higher number of individuals compared to D. esculentum. A. capillus-veneris was found to have a Shannon value of 2.149 and an evenness of 0.959, whereas D. esculentum recorded a Shannon value of 2.182 and an evenness of 0.886, respectively. This study has demonstrated the use of GIS-based mapping in representing species locations, which supports conservation and resource management strategies.